<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<style>
    body {
        padding: 0;
        margin: 0;
    }
    .table {
        background: #f5f5f5;
        /* padding: 40px; */
    }
    .item {
        display: inline-block;
        background: #ccc;
        text-align: center;
        margin: 20px;
        width: calc((100% - 80px) / 2);
        width: calc(50% - 40px);
        /* box-sizing: border-box; */
    }
</style>
<body>
    <div class="table">
        <div class="item">1</div>
        <div class="item">2</div>
        <div class="item">3</div>
        <div class="item">4</div>
        <div class="item">5</div>
        <div class="item">6</div>
    </div>
</body>
</html>